How to say "Less than 30 years ago" in Latin?

So, how would you say this…

And how can I be happy if I believe there was a massacre less than 30 years ago and less than 20 miles away from here? If it happened recently, then it can happen again, right?

…in Latin?
In Agora, I’ve phrased it this way…

However, I am almost sure that is not grammatical.

abhinc minus quam trīgintā annōs

Thanks! And is the rest of those sentences grammatical? Do you think they are understandable without the English translation?

It’s understandable. However, the protasis and the apodosis should be in the same mood (unless you consciously want to break the rule).

passuum or passibus

via a loco in quo → inde ubi


To improve your style in general, it would be good for you to go through
Latin Prose Composition, North and Hillard
Latin Prose Composition Key, North and Hillard

What are protasis and apodosis? Never heard of those, and I’ve studied quite a bit of linguistics. I haven’t studied syntax too much, though.

The protasis (if…) expresses the condition, the apodosis the consequence.
See, for example, https://en.wikipedia.org/wiki/Conditional_sentence

Does the book you recommend me, that one by Key, North and Hillard, presuppose that the reader already knows such things?

I’m not sure what you mean exactly. Have a look at the book and see if it fits your needs. P. 156 is where exercises for conditional sentences are.

How do I have a look at the book? I assumed I needed to buy it somewhere. That’s why I asked if it assumes the reader is familiar with weird vocabulary such as “protasis” and “apodosis”.

I provided links to scans of the book and the key respectively. Textkit hosts those and many other useful texts.